Background

Zinc is a trace mineral that is needed for many important functions in the body. The human body contains approximately 2-3 grams of zinc, mostly in the skeletal muscles and bones. Zinc is also found in the kidney, pancreas, retina, teeth, hair, skin, liver, blood cells, prostate, and testes.

Zinc is available through foods such as beef, pork, shellfish, peanuts, and legumes. Severe zinc deficiency may still be found in developing countries. Deficiency may cause problems with growth, diarrhea, hair loss, and immune function. Although it is rare in developed countries, some cases may be found in elderly and pregnant people. Mild zinc deficiency may be overlooked, since symptoms are not always obvious and may include loss of hair, appetite, weight, and the senses of taste and smell.

Zinc has been found to be effective for treating diarrhea, stomach ulcers, and zinc deficiency. There is good evidence to support its use for acne, ADHD, herpes simplex virus, immune function, and sickle cell anemia. Zinc has also been studied for Wilson's disease (excessive copper in the body), although results are mixed. Zinc has gained popularity for preventing the common cold, but research is still unclear.

There is still controversy on the role of zinc for many other diseases. Much evidence is conflicting or unclear.